This invention relates to a novel class of compounds having anti-androgen activity. Androgens are substances which are active in stimulating secondary sex characteristics in males. Although such substances obviously are of great physiological significance, they can produce certain undesirable side effects, and it would be highly advantageous to prophylactically or therapeutically eliminate or minimize these effects. For example, the stimulatory effects of androgens upon the prostate gland have been known for many decades. The pathogenesis of benign prostatic hypertrophy (BPH) and/or prostatic cancer (PC) is not fully understood; however, it is thought that both of these syndromes are subject to the influence of androgens. In addition, acne, an inflammatory disease involving the sebaceous glands and found chiefly in adolescents, is thought to be dependent upon sebum secretion which, in turn, is dependent upon androgen action. Other androgen-dependent conditions include hirsutism and certain types of cancer, including types of breast cancer.
Androgens are steroidal hormonal agents. For some time, it has been customary to attempt control of androgen activity by administration of other steroids. However, although administration of these steroids may be effective in diminishing androgen action, their administration in general results in other unwanted side effects which limit their usefulness. For example, cyproterone acetate is a potent steroidal anti-androgen. However, although it has demonstrated clinical effectiveness against both benign prostatic hypertrophy and prostatic cancer, it is not routinely used in humans because of its hormonal side effects. It has been reported to cause suppression of adrenal gland function as well as to exert potent progestational side effects.
It is highly desirable, therefore, to discover substances which are non-steroidal in structure and which exhibit potent anti-androgen activity. It is to such a class of compounds that this invention is directed. Only a very limited number of non-steroidal anti-androgens are recognized in the art. U.S. Pat. No. 3,857,953 discloses a class of arylidene cyclanones. These compounds are nonsteroidal, and they exhibit anti-androgen activity. It is to a new class of non-steroidal anti-androgens that this invention is directed.